Dohmen G, Tudzynski P
Institut für Botanik, Westfälische Wilhelms-Universität, Münster, Germany.
Curr Genet. 1994 Jan;25(1):59-65. doi: 10.1007/BF00712969.
Mitochondrial (mt)DNA of Secale cereale contains an open reading frame (pol-r), the potential translation product of which shows significant homology to the type-B DNA polymerase encoded by the S1 plasmid of Zea mays; it contains the highly-conserved domains IIa to V of family B polymerases. The pol-r ORF is transcribed, as proven by RT-PCR, but the transcript is not edited. Upstream of the putative start codon a potential promoter motif was detected, fitting well into the postulated consensus sequence of the transcription initiation regions of Z. mays and Triticum aestivum. The pol-r ORF occurs in mtDNA of the fertile rye variety "Halo" and the cytoplasmic male-sterile (CMS) line "Pampa". Both ORFs are almost identical, apart from the 3' terminus; pol-r from Halo can code for 289 amino acids, pol-r from Pampa for 312 amino acids. Based on codon usage and the lack of editing, pol-r is considered to be a "young" gene, probably introduced in the mtDNA of rye by recombination with an mt plasmid.
黑麦的线粒体（mt）DNA包含一个开放阅读框（pol-r），其潜在翻译产物与玉米S1质粒编码的B型DNA聚合酶具有显著同源性；它包含B族聚合酶的高度保守结构域IIa至V。经逆转录聚合酶链反应（RT-PCR）证实，pol-r开放阅读框可转录，但转录本未被编辑。在假定的起始密码子上游检测到一个潜在的启动子基序，与玉米和普通小麦转录起始区域的假定共有序列非常吻合。pol-r开放阅读框存在于可育黑麦品种“Halo”和细胞质雄性不育（CMS）系“Pampa”的线粒体DNA中。除了3'末端外，两个开放阅读框几乎相同；来自Halo的pol-r可编码289个氨基酸，来自Pampa的pol-r可编码312个氨基酸。基于密码子使用情况和缺乏编辑，pol-r被认为是一个“年轻”基因，可能是通过与线粒体质粒重组而引入黑麦线粒体DNA中的。
